<template>
  <div>
    <!-- 搜索页面头部 -->
    <div class="search-header">
      <!-- 后退按钮 -->
      <van-icon name="arrow-left" color="white" size="0.48rem" class="goback" @click="$router.back()"/>
      <!-- 搜索组件 -->
      <van-search v-focus placeholder="请输入搜索关键词" background="#007BFF" shape="round" v-model="kw" @input="inputFn" @search="enterFn"/>
    </div>
    <!-- 搜索建议列表 -->
      <div class="sugg-list" v-if="kw.length!==0">
          <div class="sugg-item" v-for="(item, index) in suggestList" :key="index"  v-html="lightFn (item, kw)" @click="clickFn(item)">

          </div>
      </div>
    <!-- 搜索历史 -->
      <div class="search-history" v-else>
          <!-- 标题 -->
          <van-cell title="搜索历史" >
              <!-- 使用 right-icon 插槽来自定义右侧图标 -->
              <template #right-icon>
      <van-icon name="delete" class="search-icon" @click="clearFn"/>
              </template>
          </van-cell>

          <!-- 历史列表 -->
          <div class="history-list" >
              <span class="history-item" v-for="(str,index) in history" :key="index" @click="clickFn(str)">{{str}}</span>
          </div>
      </div>

  </div>
</template>

<script>
import { suggestListAPI } from '@/api'
export default {
  data () {
    return {
      kw: '', // 搜索关键字
      timer: null,
      suggestList: [], // 建议关键字列表
      history: JSON.parse(localStorage.getItem('his')) || ['API', 'java', 'css', '前端', '后台接口', 'python'] // 搜索历史
    }
  },
  watch: {
    history () {
      localStorage.setItem('his', JSON.stringify(this.history))
    }
  },
  methods: {
    enterFn () {
      this.history.push(this.kw) // 保存搜索关键字
      setTimeout(() => {
        this.$router.push({
          path: `/search/${this.kw}`
        })
      })
      this.history = Array.from(new Set(this.history)) // 去重
    },
    clickFn (val) {
      this.history.push(val) // 保存搜索关键字
      setTimeout(() => {
        this.$router.push({
          path: `/search/${val}`
        })
      })
      this.history = Array.from(new Set(this.history)) // 去重
    },
    clearFn () {
      this.history = []
    },
    async inputFn () {
      clearTimeout(this.timer)
      this.timer = setTimeout(async () => {
        if (this.kw.length === 0) return // 防止空内容触发下面逻辑
        const res = await suggestListAPI({ q: this.kw })
        this.suggestList = res.data.data.options
      }, 500)
    },
    lightFn (old, traget) {
      const reg = new RegExp(traget, 'ig')
      return old.replace(reg, (match) => {
        return `<span style="color: red">${match}</span>`
      })
    }
  }
}
</script>

<style scoped lang="less">
.search-header {
  height: 46px;
  display: flex;
  align-items: center;
  background-color: #007bff;
  overflow: hidden;
  /*后退按钮*/
  .goback {
    padding-left: 14px;
  }
  /*搜索组件*/
  .van-search {
    flex: 1;
  }
}
/*搜索建议列表样式 */
.sugg-list {
  .sugg-item {
    padding: 0 15px;
    border-bottom: 1px solid #f8f8f8;
    font-size: 14px;
    line-height: 50px;
    // 实现省略号的三行代码
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    text-align: left;
  }
}
/**搜索历史 */
.search-icon {
  font-size: 16px;
  line-height: inherit;
}

.history-list {
  padding: 0 10px;
  .history-item {
    display: inline-block;
    font-size: 12px;
    padding: 8px 14px;
    background-color: #efefef;
    margin: 10px 8px 0px 8px;
    border-radius: 10px;
  }
}
</style>
